RESUMO
Hemodialysis patients have a low immune response to the hepatitis B [HB] vaccine. The method of administration plays an important role in immune response establishment. This case control study compares the efficacy of intradermal [ID] and intramuscular [IM] injection methods for the HB vaccine. This study was undertaken in hemodialysis centers. We recruited 50 patients after excluding those with histories of previous HB vaccination, immunosuppressive therapy, and who were positive for HBsAb, HBsAg, and HCV antibody. Patients were randomly assigned to receive HB vaccine by either the ID or IM injection methods. The timeline for vaccine administration was 0, 1, 2 and 6 months for both groups. The ID group received 2 microg of EngerixB in both the right and left anterolateral forearms, for a total dose of 4 microg; the IM group received 20 microg in two sites in the deltoid muscle, for a total dose of 40 microg. We measured HBsAb titers at the third and seventh months following the first doses of HB vaccine. In the third month after the first HB vaccination, 40.4% of the patients reached HBsAb levels of at least 10 mIU/ml in the ID group versus 60.9% in the IM group. At the seventh month following the first HB vaccination, 68% of patients reached HBsAb levels of at least 10 mIU/ml in the ID group versus 68% in the IM group. However the mean HBsAb titer in the ID group was 459 +/- 323.8 versus 294.6 +/- 277.5 mIU/ml in the IM group. There was no significant relation between seroconversion rates for both injection methods. However the mean titers of HBsAb for both the third and seventh months after the first HB vaccination in the ID group were more than the IM group. The cost for the low dose HB vaccine in the ID group is less than the high dose vaccine for the IM group. Thus, it is beneficial to use the ID low dose HB vaccine for underdeveloped countries.